You've posted this to 3 places now which means you really want cnc. Maybe I'm getting baited by the word "MASTERPIECE", used ironically or not.

First of all if you are going to layer tracks, play to a metronome, or at least try to stay on tempo. There are massive amounts of mistakes in the playing and a lot of the times the solo guitar and the backing guitars chords clash with each other.

Id recommend getting a cheapish audio interface (focusrite scarlet, cheap m-audio usb interfaces, etc) and a mic (sm57, sennheiser e609, etc). Practice basic recording and mixing. Then practice the song you are going to record before actually trying to record it.

When playing solo guitar, try to use some vibrato on the longer notes so it doesn't sound so flat, and if you cant tune your guitar, it at least makes it a bit better. The composition is massively average and forgettable, try to make it interesting to the listener. Think to yourself, "why would anyone want to hear this?". Also try to structure it somehow, I literally have no idea what part was supposed to be the chorus (maybe the first riff?) or the bridge?

Sounds like you've been playing guitar for maybe for a year or few months now. so if you got fired, what ever you do, don't try to make music your new job.